Filmstrip projector with synchronized sound

ABSTRACT

A control apparatus for a film strip projector provided with synchronized audio accompaniment. A recorder having a control track provides actuation signals for control of the projector motor. In response to a control signal from the recorder control track the projector motor is actuated and maintained energized through an operational movement corresponding to the advance of one film frame after which it is deactivated in ancicipation of a subsequent control signal.

United States Patent [1 1 Badalich et al. 1 Jan. 1, 1974 [54] FILMSTRIPPROJECTOR WITH 3,567,316 3/1971 Witharm 352/175 X SYNCHRONIZED SOUND3,266,862 8/1966 Wagoner 3,674,348 7/1972 Figge et al. [75] Inventors:Fran C. Badalich, g y R 3,457,005 7/1969 Goodman 352/17 Watterlohn,Morton Grove, both of I11.

[73] Assignee: Bell & Howell Company, Chicago,

Ill.

[22 Filed: Jan. 13, 1972 [21] Appl. No.: 221,464

Related U.S. Application Data [62] Division of Ser. No. 97,859, Dec. [4,1970, Pat. No.

Primary Examiner--Samuel S. Matthews Assistant Examiner-Michael L.Gellner Attorney-William K. Serp [57] ABSTRACT A control apparatus for afilm strip projector provided with synchronized audio accompaniment. Arecorder having a control track provides actuation signals for [52] U.S.CI 352/17, 352/22, 352/175 comm] f the projector motor In response to a[51] Int. Cl. G03b 31/04 0] signal from the recorder comm] track thgprojeo {58] Field of Search 352/15, l6, 17, 22, tor motor is actuatedand maintained energized 352/31, 175; 353/15 through an operationalmovement corresponding to the advance of one film frame after which itis deacti- [56] References and vated in ancicipation of a subsequentcontrol signal.

UNITED STATES PATENTS 3,620,609 11/1971 John 352/17 7 Claims, 9 DrawingFigures 276 2 4 TAPE RECORDER PLAY 2 s'gn /ecH 7 FORM/ED 210 272 gar/kmREvaesE l 256 {265 RWD ,T\ I 5 DER OFF 8555 RECDRD 3 MECH- POWER SUPPLY284 II I 286L I 9 I l MULT/ VlsRnroR 2'l6\\ I 295 OSCILLATOR NOI E PULSERELAY 0- FILTER FORMER CONTROL FILMSTRIP PROJECTOR WITH SYNCHRONIZEDSOUND This is a division of application Ser. No. 97,859, filed Dec. 14,I970.

FILMSTRIP PROJECTOR WITH SYNCHRONIZED SOUND This invention generallyrelates to a filmstrip projector and more particularly to a filmstripprojector adapted for use with a recorder providing synchronized audioaccompaniment.

BACKGROUND OF THE INVENTION Filmstrip projectors are finding wideacceptance in the instructional as well as sales promotional fields.This media is especially suitable for such purposes in that it permitsthe presentation of selected illustrations for varying time periodsdepending upon their informational content thus conserving film. It willbe appreciated that the simultaneous performance of a synchronized audiopresentation greatly increases the interest and usefulness of the visualpresentation.

The illustrated embodiment is particularly suited for the projection of35mm film but lends itself to other sizes as well. A particularcharacteristic of 35mm filmstrip is that development standards are notwell formulated throughout the industry. In this regard the sprocketholes are not precisely located with respect to the individual framespreventing the indexing of the film frames with the projection apertureby means of the sprocket hole orientation. Further, since the filmsprocket holes are not precisely related to the position of the filmframes, the advancing mechanism must be relatively exact to ensuresuitable framing throughout the entire film roll.

A particular feature of the illustrated embodiment is the inclusion of atape recorder which supplies audio accompaniment as well as a controlsignal for automatically advancing the filmstrip from frame to frame insynchronism with the audio format. Additionally, the user is affordedthe option of preparing and editing his own filmstrips. This feature isaccomplished by the addition of a signaling oscillator the output ofwhich is ap' propriately recorded as a frame advancing signal. The mainobject of this invention is to provide an improved filmstrip projectorwhich includes means for providing synchronized audio accompaniment forthe film format.

Other objects and advantages of this invention will become obvious fromthe following description of a preferred embodiment when considered inconjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a full sectional view of afilmstrip projector including certain features of this invention;

FIG. 2 is a prospective view of cartridge featured in combination withthe projector illustrated in FIG. 1;

FIG. 3 is a prospective view of the cartridge of FIG. 2 disassembled tomore clearly illustrate the features of the components thereof;

FIG. 4 is a full sectional view of the cartridge of FIG. 2 with theaudio cassette removed for clarity of illustration;

FIG. 5 is a sectiolnal view of the cartridge of FIG. 2 taken along theline 55 of FIG. 4;

FIG. 6 is a prospective view of a portion of the filmstrip projectorillustrated in FIG. 1;

FIG. 7 is a sectional view of the projector taken along the line 77 ofFIG. 1;

FIG. 8 is an enlarged sectional fragmentary view of the projector ofFIG. 1 taken along the line 88;

FIG. 9 is a symbolic diagram of the circuitry utilized to control theprojector of FIG. I.

BRIEF DESCRIPTION OF THE ILLUSTRATED EMBODIMENT -GENERAL- Briefly, therear screen filmstrip projector 10 illustrated in FIG. 1 is housedwithin a cabinet consisting of a cover 12 and a base 14. One wall of thecover is a rear projection screen 16 upon which the images aredisplayed. Housed in the base is a dual track audio cassette taperecorder 18 of modified construction carrying a cartridge 20. Uponloading of the cartridge 20 within the projector 10 the first frame ofthe filmstrip is manually framed with respect to a projection aperture22 by a manually operable framing means 24. The projector 10 isenergized causing the image of the frame centered in the projectionaperture 22 to be projected upon the screen 16. Simultaneouslytherewith, the tape recorder 18 is actuated starting the audio tapecassette play. The recorder 18 provides audio accompaniment and by afirst track carrying the audio message as well as film advance controlby means of signals recorded upon a second track. Upon the occurrence ofa control signal a frame advancing means 26 advances the filmstrip asingle frame.

Serving to prevent jamming or tearing of the film, an interlock 28prevents removal of the tape recorder while the film is threaded throughthe projector 10. Additionally, the projector 10 includes various otheroperational features which will hereinafter be more thoroughlydiscussed.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT CARTRIDGE -BASE- Thecartridge 20 carried by the tape recorder 18 is particularly illustratedin FIGS. 2-5 and comprises a cover 30 and a base 32. The base 32includes a pair of adjacent parallel oriented cassette retaining walls34 which cooperate to securely receive a conventional audio tapecassette 36. To ensure that the cassette is held in position, aretaining spring 38 engages with a pair of spring guides 40 defined bythe outwardly disposed surfaces of the cassette retaining walls 34.Additionally, projecting from the lower surface of the base 32 are apair of downwardly depending alignment pins 42 which are received inholes defined by the body of the cassette. Support wall 48 of the base32 is provided with a pair of clearance apertures 46 which allow therecord drive spindles (not shown) to fully engage the drive spools 44 ofthe cassette.

The upper surface of the support wall 48 carries a pair of spaced filmguide rails 50 the upwardly disposed edges of which are arcuatelyshaped. The ends of the rails are secured to a curved front wall 52. Theinwardly disposed surface of the front wall 52 carries two spaced pairsof sprocket hole guides 54. Each pair is secured to the wall 52 adjacentone edge thereof and serves to assure positive drive of the film as willfurther be described. Secured to the outwardly disposed surfaces of thefilm guide rails 50 adjacent the front wall are locking bosses 56 whichare selectively maintained in cooperative engagement with the cartridgecover 30. Secured to the base 32 adjacent the ends of the film guiderails opposite the locking bosses are a pair of triangular shaped hingesupports 58. lnwardly projecting from each of the hinge supports 58 arehinge pins 60 which cooperate with the cover to permit convenient accessto the interior of the cartridge 20.

- COVER The cover 30 comprises a pair of side walls 62, a rear wall 64and a top wall 66 which define a film cavity. Positioned within thecover 30 and serving to maintain the film in proper relationship withrespect to the cartridge is a film retaining means in the form of a pairof arcuately shaped resilient springs 68. The springs are fabricatedfrom elongated metallic strips or any other suitable material. One endof each of the metallic strips is turned in a reverse curve as at 70which serves to prevent scratching of the film emulsion during passageof the film from the cartridge. The remaining ends of the metallicstrips are bent in an abrupt reverse curve and are positioned withinspring receiving slots 72 moled in the rear wall 64 of the cover.Adjacent the spring receiving slots 72 in each side wall of the coverare hinge holes 74 which mate with the hinge pins 60 on the base 32.Further, locking holes 76 are punched in the side walls 62 of the cover32 and engage the locking bosses 56 on the cover. The hinge so formedpermits the cartridge 20 to be conveniently opened and the locking meansensures against accidental opening.

Rotationally supported within the cover 30 and serving to drive the filmthrough the cartridge is a film drive spool 78. The ends of the filmdrive spool 78 are journaled through apertures 80 cut in the side walls62 of the cover 30.'The film drive spool 78 includes a central hub 82and a pair of parallel spaced flanges 84. Each of the flanges 84 carriessprocket teeth 86 spaced for engagement with the sprocket holes providedalong the margins of the film. The sprocket teeth 86 are so aligned withthe sprocket hole guides 54, previously described, that as the filmpasses through the cartridge the margin of the film rides along thesprocket hole guides 54 and ensures that the sprocket teeth 86adequately engage the film. The central portion of the hub 82 ishollowed to define a splined receiver 87 for engagement with the frameadvance means 26 as will subsequently be further described. Mounted uponthe top wall 66 within the cover and adjacent the film drive spool 78are a pair of film spool guides 88 which prevent the film fromimproperly threading about the drive spool 78, a situation which mightoccur as a natural result of the curl of the emulsion. Similarly, aguide strap 90 is secured between the side walls 62 of the coveradjacent the drive spool '78 to ensure that the film will feedvertically from the cartridge rather than follow its natural curl.

- OPERATION In use, the audio tape cassette 36 is positioned in thecompartment defined by the base 32 of the cartridge 20 and is retainedin place by the locking spring 38. The cartridge is swung open on itshinges and the film, in coiled form, forced into the film retainingsprings 68.

The film is played out to the film drive spool 78 where it is engagedwith the sprocket teeth 86. The cover 30 is forced shut and locked bythe locking bosses 56 seating in the holes 76. In the closed position,the film rests upon the guide rails 50 and engages the sprocket teeth 86on the drive spool 78. The guide strap forces the film against itsnatural curl, upward along a plane generally normal to the base and thusfacilitates threading through the aperture plates on the base 14 of theprojector cabinet.

P R O J E C T O R PROJECTION SYSTEM Maintained within the base of thecabinet is a projection system which comprises a bulb 92 mounted upon abulb support channel 94, which in turn is secured to the walls 96 of anopaque light chamber. Reflecting the light toward a condenser lensassembly 98 is a reflector 100. The light passes through the film and isdirected by means of a light mirror 102 mounted upon an inner wall 104through a projection lens 106. The image is reflected by a firstreflecting mirror 108 mounted upon a mirror support stand 110 secured tothe surface of a chassis 112 mounted in the base. The image reflected bythe first mirror 108 is passed to a second reflecting mirror 114 whichis supported between adjacent cover walls subtending the included angleand therefrom directed to the projection screen 16.

-RECORDER- As shown in FIG. 7, a pair of parallel, adjacently spacedsupport rails 116, which are longitudinally notched as at 118, serve toslidably receive a tape recorder drawer 115. The outer walls of thedrawer 115 are flared outwardly to define flanges which rest within thenotches 118 in the rails 116. Within the drawer 115 is seated the audiotape cassette recorder 18. The recorder 18 is adapted to receive thecartridge 20. As previously mentioned the lower portion of the cartridge20 carries an audio tape cassette 36, which is received by the recorderin a conventional manner. Securely retaining the recorder drawer 115 inposition within the base 14 of the cabinet is an interlock 28'.

As shown in FIG. 1, interlock 28 includes a locking pawl 122 pivotablysupported for rotational movement with respect to an inner wall 124 ofthe cabinet. The pawl 122 is seated within a notch 126 defined by thewall of the recorder drawer. Manual release of the drawer is by means ofa release knob 128 accessible from the front of the cabinet andconnected to the locking pawl 122 by a locking rod 130. Biasing thelocking pawl 122 in the locked position is a coil spring 132 resting ona support angle 134 through which the rod is joumaled. Thus in responseto depression of the knob 128 the pawl 122 is rotated about its pivot ina counterclockwise direction as viewed in FIG. 1, releasing the drawerfor removal through an access door 135. Serving to ensure secure seatingof the pawl 122 with respect to the drawer 115 and thus ensure that thecartridge is properly positioned with respect to the projection apertureis a biasing means 136. The biasing means 136 urges the recorder 18 andthus the drawer in which it is seated against the holding surface of thepawl 122. The biasing means 136 includes a plunger 138 about which ispositioned a coil spring 140. The plunger is journaled through amounting angle 142 secured to the floor of the base of the cabinet.Additionally, the pawl displaces an upwardly disposed surface 144 forcooperation with an interlock mechanism as will hereinafter be furtherdescribed.

After the audio tape cassette and film are fitted in place within thecartridge 20, the cartridge is loaded into the tape recorder and therecorder drawer is slid forward until the locking pawl 122 drops intothe notch 126 in the side wall of the drawer. The biasing means 136assures that the locking pawl 122 is properly seated with respect to thedrawer 115 and thus maintains proper orientation of the cartridge 20within the projector l0,

-FILM GUIDE- As the cartridge moves into position the film is cammedbetween a pair of spaced parallel operative plates 146 and 148 mountedon the inner wall 104 which define the projection aperture 22. Servingto ensure threading of the film between the plates 146 and 148 is aspoon shaped cam 149 secured to the forwardly disposed edge of the plate148. The film, due to the natural curl of the emulsion is forced againstthe cam surface and urged into position bptween the plates.

During projection, the film is advanced through a film chute 150 andthen into a storage retainer 152 as illustrated in FIG. 7. The filmchute 150 comprises a pair of slotted rails 154 which are positioned toreceive the film passing between the aperture plates. The rails aremounted on the inner wall 104 by mounting posts 156 the outer ends ofwhich are grooved. Serving to facilitate rapid removal of the film,should it become jammed during projection, is a locking means 158 whichcomprises a flat locking plate 160 having slotted openings 162. Theouter rail 155 is positioned upon the posts 156. The plate 160 is placedover and slidably secured to the grooved end support posts 156. The filmretainer 152 includes a pair of parallel disposed spaced ear shapedreceivers 155 which has a single turn coil spring 166 secured to itsinwardly disposed surface. The coil spring 166 ensures that the storedfilm will be maintained in a nest coiled condition.

- FRAMING I As previously mentioned, a particular characteristic of afilmstrip is that the development criteria are not well established andthe location of the sprocket hole perforations along the film margin hasno predetermined position with respect to the frames. Prior to automaticoperation, the first frame of the film is properly positioned withrespect to the projection aperture 22 by the framing means 24. Servingto facilitate manual operation of the framing means 24 is a framing knob168 locked to a framing rod 170 passing into the base of the projector.As illustrated in FIGS. 6 and 8 the rod is journaled through the innersupport wall 104. Adjacent the inner end of the framing rod 170 is aselectively engageable coupling in the form of a straight tooth positiveclutch 172, including a tooth driver 194, and a slotted receiver 176.The driver 174 is set to the framing rod 170 and the slotted receiver176 is rotatably mounted .to a support angle 178 by a bushing 180through which the rod 170 is slidably journaled.

Formed upon the closed end of the receiver is a wheel gear 182 engagedwith an idler gear 184 mounted on the bracket 178. The idler gear 184 inturn engages a framing gear 186 mounted upon a film drive shaft 188. Thefilm drive shaft 188 is journaled through the inner wall 104 of thecabinet by means of a sleeve bearing 190. One end of the drive shaft 188carries a tooth member 192 (FIG. 7) of a dog-clutch which engages thesplined receiver 87 of the cartridge as film spool 78 previouslydescribed. Mounted upon the drive shaft and selectively rotatable withrespect thereto is a drive gear 194. Positioned between the drive gearand the framing gear is a friction washer 196 of resilient materialforming a friction clutch. Wound about the drive shaft and maintained inplace with a C washer 198 secured to the rearward end of the drive shaft188 is a clutch spring 200. The remaining end of the clutch spring ridesupon the face of a shoulder washer 202. The shoulder of the washer 202bears against the drive gear 194 thus assuring that during the normalposition of a spring loaded clutch arm 204 the drive gear 194 drives theframing gear 186. The clutch arm 204 is pivotably supported upon theupper surface of the chassis 112. The clutch defines an opening throughwhich the shank of the shoulder washer 202 passes. Serving to bias thefree end of the clutch arm toward the drive gear 194 is a torsion spring206.

An inward push to the framing knob pivots clutch arm 204 clockwise asviewed in FIG. 8 engaging the lips of the washer and releasing the forcewhich maintains the gears 194 and 186 in frictional engagement. Theframing gear 186 and the drive gear 194 are free to independentlyrotate. The position of the clutch arm is adjustable by an adjustmentscrew 208 threaded through the free end of the clutch arm. Coil spring210 positioned between the clutch arm and the screw head.

In use, the framing knob is forced into the base of the cabinet and thestraight tooth positive clutch 172 is engaged. Simultaneously, theclutch arm is rotated about its pivot in a clockwise direction as viewedin FIG. 8 releasing the driving frictional engagement between the drivegear 194 and the framing gear 186. Rotation of the knob 168 in itsdepressed position rotates the gear 182 and thence the idler gear 184which in turn rotates the framing gear 186. The driving member 192 ofthe dog clutch is carried upon the end of the drive shaft 188 forrotation therewith. Since the dog clutch is engaged with the splinedreceiver 87 of the film spool 78, the film is advanced. The film isdriven between the operative plates 146 and 148 until the desired imageis framed.

- FILM DRIVE The frame advance means 26 is particularly illustrated inFIG. 6 and is powered by a capacitive start reversible four pole rotorclutch motor 210. The motor includes a spring loaded rotor 212 which,during period of de-energization, is forced to a disengaged off-centerposition with respect to the armature. Secured to one end of the rotoris a coupling in the form of a cross-pin dog-clutch generally designatedby the numeral 214. Extending from end of the rotor and axially off-setis a single pin 216 which engages a cross-pin 218, passing normallythrough an indexing drive shaft 220. The shaft is journalled through adrive assembly support bracket 222. Secured to the shaft for rotation bythe motor is a worm gear 224.

Upon energization, the rotor 212 of the motor 210 is drawn into thefield of the armature. The magnetic centering of the rotor causes thecross-pin dog-clutch 214 to engage, thus driving the worm gear 224. Upondeenergization of the motor, the coupling is immediately released andthe rotor allowed to coast to a stop in disengagement. This particulararrangement is advantageous in that it allows the rotor 212 to coast toa stop without altering the position of the frame advance means 26. Apinion gear 226 is secured to an idler shaft 228 journaled in thebracket 222. Formed within the gear is the driving member 230 of ageneva drive 232.

The geneva driving member 230 includes a locking circle 234 and a drivepin 236 engaging a geneva star 238 mounted upon an indexing drive shaft240 journaled through the bracket 222 and through the inner wall 104.The axis of the shaft 240 is normal to the axis of the motor drive shaft220. The geneva star 238 is a four-pointed star so that each revolutionof the drive pin 236 will turn the drive shaft 230 through ninetydegrees. Secured to the drive shaft adjacent the inner wall 104 is anindexing shaft gear 242 which is engaged with the drive gear 194. Aspreviously mentioned, during normal operation the coil spring 200 forcesthe shoulder washer 202 against the drive gear 194 so that the gears 194and 186 are in frictional engagement. Upon energization of the motor,the geneva drive pin 236 rotates in response to an actuation pluse, tobe further described, and the driving member 230 rotates off of itscenter position illustrated in FIG. 6. A cam 244 formed upon the drivingmember 230 engages the leaf of a normally closed micro-switch 246. Themicroswitch holds the motor 210 energized through a complete revolutionof the driving member 230. As the geneva 232 completes one incrementaloperation the cam 244 again opens the micro-switch de-energizing themotor caus ing the rotor 212 to be immediately released from thearmature field. The motor 210 dynamically brakes without causing anyadditional movement of the geneva or interfering with the framingpreviously obtained. In this manner, after the initial frame has beenpositioned in the aperture 122 accurate framing is maintained throughoutprojection. After projection of the film, the motor 210 is reverseddriving the drive means 26 in the reverse direction thereby rewindingthe film back into the cartridge.

- REWIND To prevent rewind of the film to the point that the filmbecomes disengaged from the drive spool 78 of the cartridge and tofacilitate immediate replay without the need for manual framing, arewind sensing means 248 is provided. In this regard, the start of thefilm, which of course corresponds to the end of rewind, is cut with anelongated sprocket hole or rather a series of two or three sprocketholes are connected by cutting the lands between adjacent holes. Thesensing apparatus on end of rewind includes feeler 250 which rises uponthe margin of the film. The feeler 250 is journaled upon a support shaft252. The feeler carries a locking tab 254 as well as a micro-switchactuation arm 256. During normal movement of the film through theaperture 122, the feeler 250 rises along the film surface. The feeler250 is caused to rotate in a clockwise direction, as viewed in FIG. 6,thereby closing the normally open rewind micro-switch 258. During thismode of operation the locking tab 254 engages a locking tab 260 carriedby a recorder interlock feeler 262. The recorder interlock feeler 262 ispart of the film interlock 28. The feeler 262 is rotatable about theshaft 252 and biased toward the film by a torsion spring 264 (FIG. 1).The

lower end of the feeler engages the locking surface 144 of the pawl 122preventing removal of the drawer. When the film returns to itscompletely rewound position, the feeler 250, which is biased by theinternal switch spring acting through the micro-switch leaf, drops intothe elongated sprocket hole, opening the micro-switch 258 andde-actuating the motor, thus preventing further rewind. At this pointthe interlock feeler 262 is resting on the film emulsion preventingremoval of the drawer. In the event it is desired to remove the film,the framing knob 168 is pushed inwardly engaging the straight toothcoupling 172 and the film is rewound into the cartridge. The interlockfeeler 262 under the bias of the torsion spring 264 drops into theaperture 22, alowing the pawl 122 to be actuated for release of thedrawer 115.

- CONTROL CIRCUITRY With respect to FIG. 9, the tape recorder 18 ismodified to include a three-gang six position rotary switch 266 forpurposes of selecting the various modes of operation. The switch shaftis coupled to a recorder drive mechanism 266 of conventionalconstruction and serves to control the speed and direction of the tapetransport drive as determined by the position of the selector switch266. It will be appreciated that the various functions can bealternately selected by means of pushbutton switches interconnected by alocking cam, in a manner well known to those skilled in the art. Forpurposes of discussion the switch-gangs are designated as a motor gang270, a rewind gang 272 and a transducer head-gang 274. The tape recorderalso includes a conventional pick-up head, an amplifier and a speakersystem for playing back the audio accompaniment from the tapes audiotrack. However, for purposes of clarity, the conventional tape recordercircuitry has not been illustrated and will not be further described.

The wiper of the transducer gang 274 is connected to a control tracktransistor head 276 for pick-up and play-back of the film advancecontrol signals. The fixed contacts of the transducer gang in the play,forward search, reverse search, rewind and off positions areinterconnected directly to the input of an amplifier 278. In the recordposition, the transducer is connected directly to the output of anoscillator 280 which is coupled by a capacitor 282 to the input of theamplifier 278. The oscillator is triggered by means of a multivibrator284 which is activated by a switch 286. The multi-vibrator 284 pulses onthe oscillator 280 for a fixed period of time causing a pulse to beapplied to the amplifier which is recorded upon the control track of thetape.- Thus, each time the filmstrip is to be advanced the switch 286 isdepressed triggering the vibrator 284 which activates the oscillator280. The pulse is recorded on the control track of the tape and isapplied as a film advance pulse to the amplifier 278. The output of theamplifier is connected to a noise filter 288 which is utilized duringplayback to eliminate noise transients on the tape from actuating apulse former 290. The pulse former 290 is coupled to the output of thenoise filter 288. The pulse former 290 is preferably a bistablemulti-vibrator actuated by the incoming audio pulses thus providing anoutput pulse of fixed duration independent of the duration of the inputsignal. The output of the pulse former 290 activates a single polenormally open relay 292 through a relay control 294.

As will be further discussed, the period of the pulse former 290 is suchthat the motor 210 is actuated for a period of time sufficient to causethe cam surface 244 on the geneva 232 to close the micro-switch 246 sothat the locking disc 234 will complete a single revolution before themotor is turned off. A fixed contact 296 of the relay 292 is connectedto the wiper of the motor gang 270 as well as to the rewind contact onthe rewind gang 272. The fixed contact 296 is also connected to a fixedcontact 298 of the motor hold micro-switch 246. The movable contact ofthe micro-switch 246 as well as the movable contact of the relay areconnected to one pole of an on or off power switch 300 as well as to thewiper of the rewind gang 272. The remaining terminal of the on-off powerswitch is connected to a power supply 302 and the remaining terminal ofthe power supply to the common motorterminal. The forward lead of themotor is terminated atthe record, play and forward search contacts ofthe motor gang 270 and the reverse lead through the end of rewindmicroswitch 258 to the reverse-search and rewind contacts of the motorgang.

- OPERATION For purposes of discussion it will be assumed that aselected filmstrip is to be provided with audio accompaniment. The userseats the filmstrip into the film retaining springs 68 of the audiovisual cartridge cover 30 and routes the film so that the srocket holesthereof engage the sprocket teeth 86 on the film drive spool 78. Thecover is locked by the locking bosses 56 engaging the locking holes 76in the cover and an erased audiocassette cartridge is secured in placeby means of the retaining spring 38. The access door 135 is opened, thedrawer lock knob 128 depressed releasing the locking pawl and therecorder removed from the cabinet. The cartridge 20 is positioned in therecorder and the recorder 18 returned to the cabinet. The rear of therecorder 18 engages the biasing means 136 and the locking pawl 122 dropsinto the notch 126.

The user pushes the framing knob 168 against the action of the springbiased clutch releasing the drive gear 194 from frictional engagementwith the framing gear 186 and simultaneously engaging the straight toothpositive clutch 172. The knob is then rotated until the first frame ispositioned in the aperture 22 for projection. The knob is released andthe arm forces the clutch 172 out of engagement. The power supply isturned on by the switch 300 and the selector switch 266 placed in therecord mode.

The user records the desired audio-accompaniment for the frame beingprojected, and when it is desired to advance the frame, the switch 286is depressed actuating the multi-vibrator 284 which activates theoscillator 280 for a fixed period. The output of the oscillator 280 isrecorded upon the control track of the tape recorder 18 by means of thehead 276 and is also coupled through the capacitor 282 to the pulseformer 290 and relay control 294. The relay 292 is closed energizing themotor 210 which rotates in a forward direction. The relay 292 ismaintained closed for a duration corresponding to the pulse width fromthe pulse former 290 which is sufficient to assure closure of themicroswitch 246. The motor 210 continues to rotate the geneva 232through a 90 movement which is correspondingly transmitted by means ofthe drive shaft 240 to the film drive spool 78. After a completerevolution,

the switch 298 is opened by the cam 244 thus interrupting energizationof the motor 210. The spring bias on the rotor 212 of the motor 210results in the immediate disengagement of the coupling 214 allowing themotor to dynamically brake without altering the position of the film.This procedure is repeated until the entire filmstrip has been providedwith suitable audio accompaniment.

Upon completion of the recording, the user rotates the switch 266 to therewind position. In the rewind position, the rewind gang 272 connectsone output terminal of the power supply to the wiper of the motor gangwhich in turn causes the motor to operate in the reverse direction in acontinuous manner until the end of rewind micro-switch 258 is opened bythe rewind feeler 250 dropping into the elongated sprocket holepreviously described. Upon completion of the rewind feature the film isin its start position and the tape recorder is allowed to come to rest.

Normal forward play is obtained by placing the selector switch 266 inplay position wherein the control track transducer 276 is connecteddirectly to the amplifier 278. Upon the occasion of advance signal, therelay 292 is momentarily closed energizing the motor 210 in the forwarddirection. The motor is held in energization for a complete revolutionof the geneva locking disc 234 by the motor hold switch 246. When thenext successive frame reaches the projection aperture 122, themicro-switch 246 is opened deenergizing the motor.

The positioning of the selector switch 266 in the forward searchposition actuates the recorder drive mechanism 286 through themechanical coupling to a fast forward drive mode. In this position theaudio is garbled. However, the film advance pulses are fed to the motor210 and the filmstrip advanced in a rapid sequential fashion. When theoperator sees the desired frame upon the screen, he quickly places thecontrol switch in the play posi-tion and the projector continues itsnormal forward synchronized mode of operation.

In the reverse search position of the switch 266, the recorder drivemechanism 268 is switched to a fast reverse mode. The tape recorder thenoperates in a reverse direction and at each pulse the film drive motoris rotated in a reverse direction causing the film to back-frame. Whenthe user sees the desired frame, he then quickly interrupts the reversesearch by placing the switch 266 in the play position or off position.The projector is then ready for forward play.

While this invention has been particularly shown and described withreference to a preferred embodiment thereof it will be understood bythose skilled in the art that various changes in form and detail may bemade without departing from the spirit and scope of the invention.

We claim: 1. In combination with a filmstrip projector including a lightsource, a power source, a motor driving a filmstrip and means forprojecting an image provided by the filmstrip at a projection screen theimprovement comprising:

a recorder having a control track providing a control signal for theactuation of said motor; means for starting said motor in response tosaid control signal; switch means coupled to said motor for maintainingsaid motor operational through a predetermined movement corresponding tothe advance of one film frame; and

an oscillator coupled to the recording head and to said starting meansfor recording a control signal in the audio track of the recorder andsimultaneously advancing said film.

2. The apparatus of claim 1 which further includes a multi-vibratorconnected to said oscillator for control thereof so that upon activationof said multi-vibrator said oscillator will be turned on for apredetermined time period.

3. In combination with a filmstrip projector including a light source, apower source, a motor driving a filmstrip and means for projecting animage provided by the filmstrip at a projection screen the improvementcomprising:

a recorder having a control track providing a control signal for theactuation of said motor;

a first switch means for actuating said motor in response to saidcontrol signal wherein said motor is initially actuated through amovement less than a predetermined movement; and

a second switch means coupled to said motor and responsive to saidinitial actuation of said motor for maintaining said motor operationaland enabling the continuing actuation of said motor through saidpredetermined movement.

4. The apparatus of claim 3 wherein said first switch means comprises:

a relay coil energizable in response to said control signal; and

a first normally open switch wherein said first switch is closed onlywhen said relay coil is energized and wherein said motor is actuatedwhen said first switch is closed.

5. The apparatus of claim 4 wherein said second switch means comprises:

a second normally open switch connected in parallel with said firstswitch; and

a cam means coupled to said motor for closing said second switch and formaintaining said second switch closed for a predetermined time.

6. The apparatus of claim 3 wherein said starting means includes a noisefilter for removing spurious responses produced by said transducer headduring play back.

7. The apparatus of claim 6 wherein said starting means includes a pulseformer receiving said control signals and providing an output pulse inresponse thereto having a predetermined shape.

1. In combination with a filmstrip projector including a light source, apower source, a motor driving a filmstrip and means for projecting animage provided by the filmstrip at a projection screen the improvementcomprising: a recorder having a control track providing a control signalfor the actuation of said motor; means for starting said motor inresponse to said control signal; switch means coupled to said motor formaintaining said motor operational through a predetermined movementcorresponding to the advance of one film frame; and an oscillatorcoupled to the recording head and to said starting means for recording acontrol signal in the audio track of the recorder and simultaneouslyadvancing said film.
 2. The apparatus of claim 1 which further includesa multi-vibrator connected to said oscillator for control thereof sothat upon activation of said multi-vibrator said oscillator will beturned on for a predetermined time period.
 3. In combination with afilmstrip projector including a light source, a power source, a motordriving a filmstrip and means for projecting an image provided by thefilmstrip at a projection screen the improvement comprising: a recorderhaving a control track providing a control signal for the actuation ofsaid motor; a first switch means for actuating said motor in response tosaid control signal wherein said motor is initially actuated through amovement less than a predetermined movement; and a second switch meanscoupled to said motor and responsive to said initial actuation of saidmotor for maintaining said motor operational and enabling the continuingactuation of said motor through said predetermined movement.
 4. Theapparatus of claim 3 wherein said first switch means comprises: a relaycoil energizable in response to said control signal; and a firstnormally open switch wheRein said first switch is closed only when saidrelay coil is energized and wherein said motor is actuated when saidfirst switch is closed.
 5. The apparatus of claim 4 wherein said secondswitch means comprises: a second normally open switch connected inparallel with said first switch; and a cam means coupled to said motorfor closing said second switch and for maintaining said second switchclosed for a predetermined time.
 6. The apparatus of claim 3 whereinsaid starting means includes a noise filter for removing spuriousresponses produced by said transducer head during playback.
 7. Theapparatus of claim 6 wherein said starting means includes a pulse formerreceiving said control signals and providing an output pulse in responsethereto having a predetermined shape.